US9347118B2 - Alloy composition - Google Patents
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- US9347118B2 US9347118B2 US14/224,885 US201414224885A US9347118B2 US 9347118 B2 US9347118 B2 US 9347118B2 US 201414224885 A US201414224885 A US 201414224885A US 9347118 B2 US9347118 B2 US 9347118B2
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- alloy composition
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- 239000000203 mixture Substances 0.000 title claims abstract description 69
- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 64
- 239000000956 alloy Substances 0.000 title claims abstract description 64
- 239000010955 niobium Substances 0.000 claims abstract description 18
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 16
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 16
- 239000011733 molybdenum Substances 0.000 claims abstract description 16
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 16
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 16
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 10
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 10
- 229910052735 hafnium Inorganic materials 0.000 claims description 14
- 239000010936 titanium Substances 0.000 claims description 14
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 claims description 13
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 12
- 229910052719 titanium Inorganic materials 0.000 claims description 12
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 12
- 229910052721 tungsten Inorganic materials 0.000 claims description 12
- 239000010937 tungsten Substances 0.000 claims description 12
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 5
- 239000012535 impurity Substances 0.000 claims description 5
- 229910052760 oxygen Inorganic materials 0.000 claims description 5
- 239000001301 oxygen Substances 0.000 claims description 5
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims description 4
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 2
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 claims description 2
- 229910052726 zirconium Inorganic materials 0.000 claims description 2
- 238000005728 strengthening Methods 0.000 description 12
- 238000000034 method Methods 0.000 description 6
- UNASZPQZIFZUSI-UHFFFAOYSA-N methylidyneniobium Chemical compound [Nb]#C UNASZPQZIFZUSI-UHFFFAOYSA-N 0.000 description 5
- 239000006185 dispersion Substances 0.000 description 4
- 238000005242 forging Methods 0.000 description 4
- WHJFNYXPKGDKBB-UHFFFAOYSA-N hafnium;methane Chemical compound C.[Hf] WHJFNYXPKGDKBB-UHFFFAOYSA-N 0.000 description 4
- 229910052702 rhenium Inorganic materials 0.000 description 4
- WUAPFZMCVAUBPE-UHFFFAOYSA-N rhenium atom Chemical compound [Re] WUAPFZMCVAUBPE-UHFFFAOYSA-N 0.000 description 4
- 229910001182 Mo alloy Inorganic materials 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 3
- 239000006104 solid solution Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000001513 hot isostatic pressing Methods 0.000 description 2
- 229910044991 metal oxide Inorganic materials 0.000 description 2
- 150000004706 metal oxides Chemical class 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000009700 powder processing Methods 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 description 2
- 238000007545 Vickers hardness test Methods 0.000 description 1
- UMRFXKHMSJVYMY-UHFFFAOYSA-N [C].[Ti].[Zr].[Hf].[Mo] Chemical compound [C].[Ti].[Zr].[Hf].[Mo] UMRFXKHMSJVYMY-UHFFFAOYSA-N 0.000 description 1
- 210000001787 dendrite Anatomy 0.000 description 1
- 230000004992 fission Effects 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000009689 gas atomisation Methods 0.000 description 1
- -1 hafnium carbides Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C27/00—Alloys based on rhenium or a refractory metal not mentioned in groups C22C14/00 or C22C16/00
- C22C27/04—Alloys based on tungsten or molybdenum
Definitions
- the present invention relates to an alloy composition, particularly though not exclusively, to an alloy composition suitable for use in refractory (i.e. high temperature) applications.
- the invention further relates to a forging die comprising the alloy composition.
- Prior alloy compositions comprising molybdenum are known, particularly for use in refractory applications such as fusion and fission reactors, rocket engine nozzles, furnace structural component and forging dies. Such applications require high hardness (as measured according to the Vickers hardness test) at a particular operating temperature.
- known molybdenum based alloy compositions have insufficient strength for some applications, particularly at high temperatures such as 1000 to 1100° C., and may have a high cost of production.
- compositions of prior molybdenum based alloys are given in table 1, given in terms of weight percentages.
- TZM is described in further detail in U.S. Pat. No. 3,275,434.
- Further prior molybdenum based alloys are described in “The Engineering Properties of Molybdenum Alloys” by F F Schmidt and H R Ogden.
- Rhenium containing alloys may therefore have an unacceptably high cost.
- the present invention describes an alloy composition and an article comprising the alloy composition which seeks to overcome some or all of the above problems. All percentage amounts are given in terms of weight percentages unless otherwise specified.
- an alloy composition comprising molybdenum, wherein the composition comprises between 15% and 20% niobium and 0.05% and 0.25% carbon.
- the described alloy has a high hardness at temperatures of between 1,000 and 1,100° C., and is consequently suitable for a wide range of uses, including for example refractory articles.
- the relatively high amount of niobium compared to prior compositions has been found to form niobium carbide (HfC), which acts as a strengthener.
- niobium is a relatively inexpensive element in comparison to other strengtheners, resulting in an alloy composition having a high strength at the required temperatures, and a relatively low overall cost.
- the alloy composition may comprise between 16% and 17% niobium, and may comprise between 16.1 and 16.5% niobium, and preferably may comprise approximately 16.3% niobium.
- the alloy composition may further comprise hafnium, and may further comprise between 0.5% and 4% hafnium, and may comprise between 0.7% and 0.9% hafnium, and preferably may comprise approximately 0.8% hafnium.
- hafnium carbide acts as a strengthener in addition to the strengthening provided by the niobium carbide.
- HfC hafnium carbide
- sufficient strengthening may be provided only by niobium.
- hafnium can be used to provide further strengthening, though at a comparatively high cost.
- the alloy may further comprise titanium, and may comprise between 1% and 3% titanium, may comprise between 1.3% and 1.5% titanium, and may comprise substantially 1.42% titanium.
- the titanium may be in the form of titanium oxide (TiO 2 ). TiO 2 has been found to further increase the strength of the alloy by providing dispersion strengthening, and/or solid solution strengthening.
- the alloy may further comprise tungsten, and may comprise between 1% and 10% tungsten, may comprise between 2.7% and 2.9% tungsten, and may comprise substantially 2.8% tungsten.
- tungsten is thought to act as a solid solution strengthener, thereby increasing the strength of the alloy.
- the balance of the composition may comprise molybdenum.
- the alloy may further comprise incidental impurities.
- the alloy may consist substantially only of molybdenum, niobium, titanium, carbon, hafnium, tungsten, oxygen and incidental impurities.
- the alloy composition may further comprise oxygen or metal oxides.
- the presence of metal oxides in the alloy composition is thought to provide dispersion solution strengthening, which will further increase the strength of the alloy.
- the alloy composition may have an ultimate tensile strength of between approximately 380 MPa and 460 MPa at a temperature of 1,000° C.
- an article comprising an alloy composition in accordance with the first aspect of the invention.
- the article may comprise a forging die.
- the alloy is particularly suitable for in use in a forging die, since the alloy provides a very high strength at high temperatures.
- Table 2 describes an alloy composition in accordance with the present invention
- Table 3 describes an example of an alloy composition in accordance with the present invention.
- FIG. 1 is a graph comparing the relationship between the temperature and the ultimate tensile strength of compositions described in tables 1 and 3;
- FIG. 2 shows a back scattered electron image of the microstructure of the composition described in table 3.
- Table 2 shows the compositional ranges of an alloy composition
- table 3 shows an example composition of the first alloy composition.
- a back scattered electron image of the microstructure of the composition of table 3 is shown in FIG. 2 .
- the nominal alloy composition is thought to have an ultimate tensile strength (UTS) of between approximately 380 MPa and 460 MPa at a temperature of 1,000° C., which is supported by evidence from Vicker's hardness tests. This is an improvement in UTS of approximately 50 to 250 MPa at a temperature of 1,000° C. compared to prior molybdenum based alloy compositions such as TZM.
- UTS ultimate tensile strength
- This is an improvement in UTS of approximately 50 to 250 MPa at a temperature of 1,000° C. compared to prior molybdenum based alloy compositions such as TZM.
- an alloy composition comprising molybdenum, between 15% and 20% niobium and 0.05% and 0.25% carbon provides advantages over prior molybdenum alloy compositions.
- niobium carbide NbC
- the niobium carbide in the composition is responsible for the majority of the strengthening effects.
- hafnium in the amounts specified in table 2 is thought to further increase the strength of the composition at both high and low temperatures, both by forming hafnium carbides (HfC) and solid solution strengthening.
- titanium in the specified amounts promotes the formation of dispersion strengthening titanium dioxide (TiO 2 ), which has the effect of further increasing the strength of the alloy composition.
- tungsten carbide has a relatively small contribution to the strengthening of the composition, and so may optionally be omitted from the composition, particularly in view of the increased processing costs inherent in tungsten containing alloy compositions. Indeed, an alloy comprising only molybdenum, hafnium and carbon in the amounts specified is necessary to provide an alloy having superior tensile strength at high temperatures relative to prior alloys.
- the composition may further comprise a trace amount of zirconium.
- the alloy is produced by a powder processing method.
- the powder processing method comprises melting and gas atomisation to form particles having a diameter of less than approximately 5 ⁇ m.
- a billet is then formed by hot isostatic pressing (HIP) of the particles.
- HIP hot isostatic pressing
- the powder is subjected to heat at temperatures of approximately 2000° C. at approximately 100 Mpa for approximately 4 hours.
- FIG. 2 shows a sample of alloy having the composition described in table 3.
- the sample was produced using an arc-cast method.
- the lighter areas of the sample are hafnium carbide precipitates within the alloy matrix.
- the hafnium carbide precipitates are segregated to the interdentritic regions with molybdenum rich primary dendrites in the sample. More uniform, fine dispersions of hafnium carbide can be produced using a powder metallurgy process. This will be expected to improve the properties of the alloy further.
- the composition may comprise further elements.
- the alloy may be formed using different processes.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Powder Metallurgy (AREA)
Abstract
Description
TABLE 1 |
Prior Compositions (weight percent) |
Titanium | Carbon | Zirconium | Hafnium | Molybdenum | ||
TZM | 0.5 | 0.02 | 0.08 | — | Balance |
TZC | 1.3 | 0.1 | 0.3 | — | Balance |
MHC | — | 0.05-1.5 | — | 0.8-1.4 | Balance |
ZHM | — | 0.12 | 0.4 | 1.2 | Balance |
TABLE 2 | |||
wt. % |
Max | Min | ||
Mo | bal. | bal. | ||
Nb | 17 | 16 | ||
Ti | 1.5 | 1.3 | ||
C | 0.15 | 0.25 | ||
Zr | — | — | ||
Hf | 0.9 | 0.7 | ||
W | 2.9 | 2.7 | ||
TABLE 3 | ||
wt. % | ||
Mo | bal. | ||
Nb | 16.3 | ||
Ti | 1.42 | ||
C | 0.2 | ||
Zr | — | ||
Hf | 0.8 | ||
W | 2.8 | ||
Claims (13)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB1307535.3 | 2013-04-26 | ||
GBGB1307535.3A GB201307535D0 (en) | 2013-04-26 | 2013-04-26 | Alloy composition |
Publications (2)
Publication Number | Publication Date |
---|---|
US20140322068A1 US20140322068A1 (en) | 2014-10-30 |
US9347118B2 true US9347118B2 (en) | 2016-05-24 |
Family
ID=48626870
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US14/224,885 Active 2034-11-15 US9347118B2 (en) | 2013-04-26 | 2014-03-25 | Alloy composition |
Country Status (3)
Country | Link |
---|---|
US (1) | US9347118B2 (en) |
EP (1) | EP2796581B1 (en) |
GB (1) | GB201307535D0 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10597757B2 (en) * | 2014-04-23 | 2020-03-24 | Questek Innovations Llc | Ductile high-temperature molybdenum-based alloys |
Citations (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB670555A (en) | 1946-04-12 | 1952-04-23 | Jessop William & Sons Ltd | Improvements in or relating to nickel-chromium steels |
US2850385A (en) * | 1955-08-29 | 1958-09-02 | Universal Cyclops Steel Corp | Molybdenum-base alloy |
US3184834A (en) * | 1961-12-19 | 1965-05-25 | Du Pont | Selected mo-nb-si-ti compositions and objects thereof |
US3275434A (en) | 1964-04-13 | 1966-09-27 | Gen Electric | Molybdenum-base alloy |
US3479155A (en) | 1962-11-20 | 1969-11-18 | Schwarzkopf Dev Co | Heat-shock resistant shaped high temperature metal ceramic bodies |
DE3530837A1 (en) | 1985-08-29 | 1987-03-05 | Soudbrase Schweisstech Gmbh | Welding rod |
US5082625A (en) | 1987-01-14 | 1992-01-21 | Toyota Jidosha Kabushiki Kaisha | Corrosion-resistant alloy for build-up welding |
JPH05171340A (en) | 1991-12-26 | 1993-07-09 | Sumitomo Metal Ind Ltd | Ni-w alloy excellent in corrosion resistance and wear resistance |
JPH05179378A (en) | 1991-12-27 | 1993-07-20 | Sumitomo Metal Ind Ltd | Ni-based alloy with excellent room temperature and high temperature strength |
US5316723A (en) | 1992-07-23 | 1994-05-31 | Reading Alloys, Inc. | Master alloys for beta 21S titanium-based alloys |
US6066191A (en) * | 1997-05-21 | 2000-05-23 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Hard molybdenum alloy, wear resistant alloy and method for manufacturing the same |
US6248292B1 (en) * | 1998-02-25 | 2001-06-19 | Toyota Jidosha Kabushiki Kaisha | Overlay welding alloy and engine valve overlayed therewith |
US20090136381A1 (en) | 2007-11-23 | 2009-05-28 | Rolls-Royce Plc | Ternary nickel eutectic alloy |
US20120003486A1 (en) * | 2010-06-30 | 2012-01-05 | H.C. Starck, Inc. | Molybdenum containing targets |
-
2013
- 2013-04-26 GB GBGB1307535.3A patent/GB201307535D0/en not_active Ceased
-
2014
- 2014-03-25 US US14/224,885 patent/US9347118B2/en active Active
- 2014-03-25 EP EP14161529.4A patent/EP2796581B1/en not_active Not-in-force
Patent Citations (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB670555A (en) | 1946-04-12 | 1952-04-23 | Jessop William & Sons Ltd | Improvements in or relating to nickel-chromium steels |
US2850385A (en) * | 1955-08-29 | 1958-09-02 | Universal Cyclops Steel Corp | Molybdenum-base alloy |
US3184834A (en) * | 1961-12-19 | 1965-05-25 | Du Pont | Selected mo-nb-si-ti compositions and objects thereof |
US3479155A (en) | 1962-11-20 | 1969-11-18 | Schwarzkopf Dev Co | Heat-shock resistant shaped high temperature metal ceramic bodies |
US3275434A (en) | 1964-04-13 | 1966-09-27 | Gen Electric | Molybdenum-base alloy |
DE3530837A1 (en) | 1985-08-29 | 1987-03-05 | Soudbrase Schweisstech Gmbh | Welding rod |
US5082625A (en) | 1987-01-14 | 1992-01-21 | Toyota Jidosha Kabushiki Kaisha | Corrosion-resistant alloy for build-up welding |
JPH05171340A (en) | 1991-12-26 | 1993-07-09 | Sumitomo Metal Ind Ltd | Ni-w alloy excellent in corrosion resistance and wear resistance |
JPH05179378A (en) | 1991-12-27 | 1993-07-20 | Sumitomo Metal Ind Ltd | Ni-based alloy with excellent room temperature and high temperature strength |
US5316723A (en) | 1992-07-23 | 1994-05-31 | Reading Alloys, Inc. | Master alloys for beta 21S titanium-based alloys |
US6066191A (en) * | 1997-05-21 | 2000-05-23 | Kabushiki Kaisha Toyota Chuo Kenkyusho | Hard molybdenum alloy, wear resistant alloy and method for manufacturing the same |
US6248292B1 (en) * | 1998-02-25 | 2001-06-19 | Toyota Jidosha Kabushiki Kaisha | Overlay welding alloy and engine valve overlayed therewith |
US20090136381A1 (en) | 2007-11-23 | 2009-05-28 | Rolls-Royce Plc | Ternary nickel eutectic alloy |
EP2065479A2 (en) | 2007-11-23 | 2009-06-03 | ROLLS-ROYCE plc | A ternary nickel eutectic alloy |
US20120003486A1 (en) * | 2010-06-30 | 2012-01-05 | H.C. Starck, Inc. | Molybdenum containing targets |
Non-Patent Citations (3)
Title |
---|
British Search Report issued in British Patent Application No. GB1307535.3 on Oct. 2, 2013. |
Schmidt, F.F., et al., "The Engineering Properties of Molybdenum Alloys," 9 pages. |
Sep. 12, 2014 Search Report issued in European Application No. 14161529. |
Also Published As
Publication number | Publication date |
---|---|
US20140322068A1 (en) | 2014-10-30 |
EP2796581B1 (en) | 2018-05-09 |
EP2796581A1 (en) | 2014-10-29 |
GB201307535D0 (en) | 2013-06-12 |
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